The No. 1 midsize place to work in IT may be an 11-year-old company with nearly 3,500 employees, yet LinkedIn still very much has the look and feel of a laid-back and oh-so-cool Silicon Valley startup.

Workers cruise around the company's grassy, college-like campus in Mountain View, Calif., on colorful beach bikes, which are stowed in racks outside each entrance and are free for the riding. There's free, made-to-order food in the cafe, an on-site health club offering strength training equipment and yoga and kickboxing classes, plus legendary parties hosted by IT, which has been known to transform the workplace into a full-on nightclub.

"There are a lot of benefits, like the cool parties when we get to keep the culture happy and entertaining," says 25-year-old Sridevi Rajaraman, who was hired after college graduation and now, as an IT business partner, works with business users on adopting new technologies.

"But the biggest reason I like this job is that it's different every day," she says. "There are different business problems, and I'm really happy to be part of an IT department that has the attitude and intention to help our employees be more productive."

A commitment to customer service is absolutely imperative for anyone working in IT at LinkedIn. So are unparalleled technical chops and, perhaps surprisingly, social skills.

When hiring, "the very first thing we look for is technical skill, but almost as important is how well a person interacts with others," says Mike Jennings, senior director of LinkedIn's $31 million enterprise IT organization. "If someone is extremely intelligent on the technical side but isn't up to par on interaction, we discount them. We have found that's our best bet. Otherwise, you spend too much time trying to teach a person soft skills."

Being a pleasure to do business with is a point of pride for IT at LinkedIn. IT support analysts are available in tech lounges where users are encouraged to make themselves comfortable in beanbag chairs and listen to music as they get their computing problems solved.

When he moved into the top IT role six years ago, Jennings says he was determined to build an IT group with deep customer service skills. The company recruits through LinkedIn and by word of mouth exclusively and offers referral bonuses to employees as an incentive.

"What I remember most is not wanting to build a department where everybody hates to do business with IT. I've worked at companies where IT was despised and they sat in dark corners," he says. So first and foremost, Jennings was on the lookout for people with impressive customer service skills. "Once I started hiring those people, it started propagating out and they brought in people who were similar," he says. Now nontechnical employees view IT as a benefit, on par with the company's free lunches, Jennings says.

The attrition rate among IT staffers is 8% -- "very low," Jennings notes -- perhaps owing to the four weeks of paid time off that employees receive after one year of service or the fully paid health insurance that everyone gets from the start. Or maybe it's the profit-sharing plan, the stock options, the overtime pay or the individual employee bonuses.

There's also plenty of room to grow at LinkedIn. IT had a training budget of $350,000 last year for its 112 employees. Additionally, each year employees are reimbursed up to $5,000 in tuition costs and/or the cost of technology certifications.

And LinkedIn is expanding globally, which creates opportunities. IT hired 50 new employees and promoted 17% of its IT employees in the past year.

Senior director of IT Mike Jennings, right, goes in for extreme team-building with IT staffers Chris Arrington and Alex Lacayo. When hiring, Jennings says he pays close attention to "how well a person interacts with others."

Campbell Pool joined the company two and a half years ago as a support analyst and has since moved up to become a systems engineer in virtualization. "One of the company values is personal and professional promotion, and we really do that quite well," he says.

Earlier this year, Pool took a weeklong training course in new VMware technologies. "It's definitely my experience that you can see what you want to do, then work with your manager to take the next steps to get there in your career," he says.

Career growth and promotion opportunities are exactly what drew Utkarsh Contractor -- whose title is "growth hacker" -- to LinkedIn 10 months ago.

"I wanted a place that would listen to my career growth aspirations," he says. "LinkedIn gives you room to work outside of your responsibilities and venture into different areas."

Contractor's regular job is building search and collaboration systems for internal use by LinkedIn employees. But he also has a keen interest in developing analytics tools and has been able to work on those projects as well. "You're not restricted by a particular set of technologies," Contractor says. "If you think that things are not as they should be, you can reach out and make changes. Your job is not to stick to scope."

Another way that LinkedIn promotes professional development is through the monthly "InDays" when staffers can drop their regular duties to explore new ideas, hack with friends or volunteer for special causes. Rajaraman spent one recent InDay mentoring high school students on how to update their LinkedIn profiles to improve their odds of getting into college and gaining the skills they need to join a technology company.

The company also offers what it calls Transformation Grants to employees working on projects designed to "transform themselves, their communities and their world." One recipient, Alex Lacayo, a media productions manager in the IT department, was awarded $3,000 for his work with Playing for Change, a movement created to inspire and connect the world through music.

"We raised over $9,000 for this cause that I believe in so much," Lacayo says. "To have my company back me up like that is an incredible thing."